Radeon HD 6990 4GB Power and Thermals

Power Consumption (Idle and Gaming)

Putting a realistic, repeatable load on a GPU to get a decent idea of its real world power consumption and thermal output has long been something with which we've experimented at bit-tech. We've found that synthetic benchmarks such as FurMark thrash the GPU constantly, which simply isn't reflective of how a GPU will be used when gaming.

It's such a hardcore test that any GPU under test is almost guaranteed to hit its thermal limit, the mark at which the card's firmware will kick in, speeding up the fan to keep the GPU within safe temperature limits. Conversely, simply leaving a game such as Crysis running at a certain point also isn't reflective of real world use. There's no guarantee that the GPU is being pushed as hard as other titles might push it, and the load will vary from play-through to play-through.

Eventually, we decided to use 3DMark06's Canyon Flight test as a real world representative, repeatable graphics test. It's a ferociously demanding test, pushing graphics cards to their limit, but it also contains peaks and troughs in performance that match real world game play.

As the test is so demanding and GPU limited, we've set 3DMark to run the test at 1,280 x 1,024 with 0xAA and 16xAF (enabled in the driver), constantly looping the test for thirty minutes and recording the maximum power consumption and GPU Delta T (the difference between the temperature of the GPU and the ambient temperature in our labs).